Create factorial_iterative.py

maths/factorial_iterative.py

@@ -0,0 +1,23 @@
+def factorial_iterative(number: int) -> int:
+    """
+    Return the factorial of a non-negative integer using an iterative method.
+
+    >>> factorial_iterative(5)
+    120
+    >>> factorial_iterative(0)
+    1
+    >>> factorial_iterative(1)
+    1
+    """
+    if number < 0:
+        raise ValueError("Input must be a non-negative integer")
+
+    result = 1
+    for i in range(2, number + 1):
+        result *= i
+    return result
+
+
+if __name__ == "__main__":
+    # simple demonstration
+    print(factorial_iterative(5))  # expected 120

maths/gcd_iterative.py

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+def gcd_iterative(a: int, b: int) -> int:
+    """
+    Compute the greatest common divisor (GCD) of two numbers iteratively.
+
+    Examples:
+    >>> gcd_iterative(48, 18)
+    6
+    >>> gcd_iterative(7, 5)
+    1
+    """
+    while b != 0:
+        a, b = b, a % b
+    return a